Welcome Guest. Sign in or Signup

4 Answers

does temperature inversion bring wind shear?

Asked by: 6709 views
Weather

Hi yall, I've always thought that whenever there's a temperature inversion, there's a high possibility of windshear.

But today I read in my ATP book it says,

"If the temperature actually increases as altitude increases, a temperature inversion exists. This is the most sable of weather conditions."

And before this paragraph it was about if temperature drops at a much faster rate than the normal lapse rate, the more unstable the air will be.

So, what is it that I'm not understanding? Eventhough the air can be stable, but there could be windshear?

 

I appreciate in advance for all the help!

Karl

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

4 Answers



  1. Mark Kolber on Feb 16, 2016

    Perhaps you are not understanding the difference between an inversion in which the ambient temperature increases, instead of decreases, with altitude and a situation in which the temperature decreases faster than the lapse rate.

    This is a very simplistic picture of the more complicated “parcel theory” but I think it illustrates the point: Think of a small balloon that is filled with air that is kept exactly at the lapse rate temperature. What will it do when it is colder than the surrounding air? What will it do when it is warmer than the surrounding air? In the first situation, the parcel of stable air rises (just like thunderstorms develop). In the second, it doesn’t rise at all and may actually sink.

    It might help to picture how a hot air balloon rises and falls as you use the torch to increase its temperature and then let it cool.

    0 Votes Thumb up 1 Votes Thumb down 1 Votes



  2. Mark Kolber on Feb 16, 2016

    That was incomplete. Air stability is generally a vertical measure – how that balloon rises and falls. Wind shear is mostly a horizontal measure. That horizontal measure produces shear when the boundary line between the warmer air of the inversion and the colder non-inversion air is relatively small. It’s the change from one to another that contains the change in wind direction and intensity.

    +2 Votes Thumb up 2 Votes Thumb down 0 Votes



  3. Tijmen de Boer on Feb 16, 2016

    Yes, it is a matter of density, thickness of the air. In fact all inversions give a kind of difference between windspeed and winddirection. Shears are often light, but may moderate ore more. The difference between convective or turbulence shears and this one, is that inversion shear stay at the same place and keep the same strengh for long time. So the inversion-shear is so to say stable😉 AND the air is very stable.
    Inversion shear are most hazardes near the surface and for the bigger planes, say wide bodies. We warn in aviation for strong low level inversions when they are more than 10 deg C below 1500 feet. Strong windshear is then possible and may be hazardous. Think of nice radiation weather in wintertime and warm air aloft.
    Gr Tim
    Senior aviation forecaster Amsterdam

    0 Votes Thumb up 1 Votes Thumb down 1 Votes



  4. Tijmen de Boer on Feb 16, 2016

    And not only the windshear can be hazardes, but also the T difference: when a heavy plane takes off and within say 300 feet the T rises 10+ degrees, the performance of the aircraft drops dramaticly…
    I haven often seen low level inversions of more than 10 degrees (10-15 degr max) in 500 feet!
    Gr Tim

    0 Votes Thumb up 1 Votes Thumb down 1 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.